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271.
Insulin-dependent diabetic children and a group of their nondiabetic peers were compared on measures of self-concept, locus of control and health locus of control. A metabolic measure of long term diabetes control was also obtained on the children with diabetes. Data analyses revealed that metabolic control was not related to any of the personality measures in the diabetic sample. Diabetic and non-diabetic children did not differ on measures of locus of control and self-concept, but diabetics exhibited a health locus of control which was significantly more internal than that of control subjects. A possible explanation for these results was discussed and practical implications for health care providers working with young diabetics were presented.  相似文献   
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Experiment 1: In a specialized daycare program the use of oral overcorrection (contingent toothbrushing with an oral antiseptic) to suppress one child's thumbsucking at Language Time was found to suppress the behavior of another child who was not treated but who witnessed the target child's treatment. Experiment 2: The main effects of oral overcorrection were replicated. Contingent overcorrection threats (warnings), used independently, were then shown to suppress thumbsucking behavior that had returned to its baseline level. These effects were maintained one month after the threats were discontinued, but they did not generalize to other activity periods, particularly Nap Time. Experiment 3: Contingent threats were found to suppress the persistent nap-time thumbsucking of the child from Expt 2. Increments in certain other (nonoral) inappropriate behaviors were correlated with the suppression of thumbsucking. Threats to use oral overcorrection contingent upon nonoral misbehaviors at Nap Time were not effective. However, the actual use of oral overcorrection for these categories of nonoral misbehavior served to suppress these behaviors. Experimental controls combined treatment reversal and multiple baseline single-subject designs.  相似文献   
274.
In contrast to a recent finding (Macdonald, G. E., & De Toledo, L. Learning and Motivation, 1974, 5, 288–298.) the results of three experiments investigating various partial reinforcement (PRF) manipulations under conditions of thirst motivation demonstrated strong similarity to analogous manipulations involving food reward. Specifically, for animals receiving water reinforcement, PRF was shown to generate greater resistance to extinction than continuous reinforcement (Expt 1 & 3), the schedule of reinforcement was shown to interact with level of acquisition (Expt 1 and 2), and the magnitude of the partial reinforcement extinction effect was shown to be a function of reward magnitude (Expt 3). These results provide strong evidence that mechanisms which operate in partial reinforcement situations are highly similar, regardless of the type of appetitive reinforcement.  相似文献   
275.
C. S. Jenkins has recently proposed an account of arithmetical knowledge designed to be realist, empiricist, and apriorist: realist in that what’s the case in arithmetic doesn’t rely on us being any particular way; empiricist in that arithmetic knowledge crucially depends on the senses; and apriorist in that it accommodates the time-honored judgment that there is something special about arithmetical knowledge, something we have historically labeled with ‘a priori’. I’m here concerned with the prospects for extending Jenkins’s account beyond arithmetic—in particular, to set theory. After setting out the central elements of Jenkins’s account and entertaining challenges to extending it to set theory, I conclude that a satisfactory such extension is unlikely.  相似文献   
276.
A number of influential reports on influenza pandemic preparedness include recommendations for extra-autonomous decisions to withdraw mechanical ventilation from some patients, who might still benefit from this technology, when demand for ventilators exceeds supply. An unintended implication of recommendations for nonvoluntary and involuntary termination of life support is that it make pandemic preparedness plans vulnerable to patients' claims for assisted suicide and active euthanasia. Supporters of nonvoluntary passive euthanasia need to articulate why it is both morally different and morally superior to voluntary active euthanasia if they do not wish to invite expansion of end-of-life options during health system catastrophe.  相似文献   
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The rate of habituation to food is inversely related to energy intake, and overweight children may habituate slower to food and consume more energy. This study compared patterns of sensitization, as defined by an initial increase in operant or motivated responding for food, and habituation, defined by gradual reduction in responding, for macaroni and cheese and pizza in overweight and non-overweight 8- to 12-year-old children. Non-overweight children habituated faster to both foods than overweight children (p = .03). All children recovered motivated responding for a new food (chocolate). Overweight children consumed more energy than non-overweight children (p = .0004). Children who showed a sensitization in responding consumed more food (p = .001), and sensitization moderated the effect of overweight on habituation, with slower habituation for overweight children who sensitized (p < .001). This study replicates previous data on overweight/non-overweight differences in habituation of food and energy intake, and provides new information that individual differences in sensitization and habituation of motivated responding to obtain food may be associated with a sustained motivation to eat, resulting in greater energy intake.  相似文献   
280.
When two targets are presented within approximately 500 ms of each other in the context of rapid serial visual presentation (RSVP), participants’ ability to report the second target is reduced compared to when the targets are presented further apart in time. This phenomenon is known as the attentional blink (AB). The AB is increased in magnitude when the first target is emotionally arousing. Emotionally arousing stimuli can also capture attention and create an AB-like effect even when these stimuli are presented as to-be-ignored distractor items in a single-target RSVP task. This phenomenon is known as emotion-induced blindness (EIB). The phenomenological similarity in the behavioral results associated with the AB with an emotional T1 and EIB suggest that these effects may result from similar underlying mechanisms – a hypothesis that we tested using event-related electrical brain potentials (ERPs). Behavioral results replicated those reported previously, demonstrating an enhanced AB following an emotionally arousing target and a clear EIB effect. In both paradigms highly arousing taboo/sexual words resulted in an increased early posterior negativity (EPN) component that has been suggested to represent early semantic activation and selection for further processing in working memory. In both paradigms taboo/sexual words also produced an increased late positive potential (LPP) component that has been suggested to represent consolidation of a stimulus in working memory. Therefore, ERP results provide evidence that the EIB and emotion-enhanced AB effects share a common underlying mechanism.  相似文献   
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